Did you know that there’s a whole set of abdominal muscles behind your six pack? It’s called the transverse abdominis (TVA), and when you work to strengthen it, it can do some wonderful things: Support your spine during heavy lifts, improve your posture, and even hold your tummy in tighter to your body for a slimmer waistline.

The only problem is the TVA isn’t fully activated during normal crunches and sit ups. But there is a really powerful (and convenient!) way to work the transverse abdominis anytime, anywhere. It’s called the stomach vacuum exercise.

With a little practice and a lot of consistency, the stomach vacuum can have some massive effects on your midsection: Toning, tightening, strengthening, and giving you that flat midsection you’ve been craving. This infographic from The Trusty Spotter explains how to do the stomach vacuum and why it’s such a good addition to any core workout routine

Stomach Vacuums